feat: add customer profile candidate flow

tests/unit/service/test_memory_service.py

@@ -116,6 +116,24 @@ async def test_upsert_persists_structured_value_when_created() -> None:
     assert created.memory_key == "preference:risk_level"
 
 
+@pytest.mark.asyncio
+async def test_upsert_candidate_never_updates_active_memory() -> None:
+    """候选写入不读取或覆盖同键正式记忆，等待确认后再晋升。"""
+    session = fake_session()
+    session.scalar.side_effect = [None]
+    added: list[Any] = []
+    session.add = Mock(side_effect=added.append)
+
+    created = await MemoryService(session).upsert(
+        7, "preference:risk_level", "稳健型", memory_type="preference",
+        confidence=0.9, status="candidate",
+    )
+
+    assert created.status == "candidate"
+    assert created.content == "稳健型"
+    assert added == [created]
+
+
 @pytest.mark.asyncio
 async def test_upsert_refreshes_structured_value_on_existing_memory() -> None:
     existing = memory(5, key="preference:risk_level", content="保守型")